If all of the lots are drawn just simply copy a piece of text into the correct place on the first one.
When you are happy that you have the text in the correct place with the correct font and size etc. simply copy it to every "lot" that you wish to auto number.
Next you need to use the Automatic text Numbering from the Express pull down menu.
Select each piece of text that you want to be in the number sequence and enter (note. if you select them in order the numbering can follow the same order)
Next you will be asked for which order to number in. If you use select_order that will number in the order you picked them.
Then you can set the starting number followed by the increment.
Then finally you can select how you wanyt the numbering, i.e as a suffix or prefix or overwrite the complete text with the new number.
Hope that helps. have a play and see what you get. I have used it a lot and it is quite useful.
There may be some way of automating this with some form of Lisp routine but I have never needed more than express tools can give.